ABSTRACT: Nanographite flake through ultrasound dispersing expanded graphite which got by chemical oxidation and microwave puffing method have been prepared by natural flake graphite. The microstructures of natural flake graphite, expanded graphite and nanographite sheets were characterized by means of SEM, XRD, FTIR and Raman; the cathodes were made by NG, EG and nanographite, respectively; the electrolysis phenol was conducted by the diaphragm cell prepared cathode and the Ti/RuO2 anode. The results showed that the thickness of graphite flake was 18 nm, and the grain size and particle size decreased compared with the NG and EG; Nano-G showed the best electrochemical properties; in the diaphragm electrolysis system with the aeration conditions, the degradation rate of phenol reached 89.5% COD reached 81.3% under 120 min’s electrolysis, which was far above the degradation rate of phenol of EG cathode and NG cathode.